32 lines
637 B
C
32 lines
637 B
C
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#include "sst_crc.h"
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unsigned int sst_crc32(unsigned int crc, void *buffer, unsigned int length)
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{
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unsigned int i, j;
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crc32_data_t crc32;
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unsigned int crc32_calc = 0xffffffff;
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crc32.crc = crc;
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for (i = 0; i < 256; ++i) {
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crc32.crc = i;
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for (j = 0; j < 8; ++j) {
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if (crc32.crc & 1)
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crc32.crc = (crc32.crc >> 1) ^ 0xedb88320;
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else
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crc32.crc >>= 1;
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}
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crc32.crc_32_tbl[i] = crc32.crc;
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}
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crc32_calc = 0xffffffff;
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for (i = 0; i < length; ++i) {
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crc32_calc =
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crc32.
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crc_32_tbl[(crc32_calc ^ ((unsigned char *)buffer)[i]) & 0xff] ^
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(crc32_calc >> 8);
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}
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return crc32_calc ^ 0xffffffff;
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}
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